In the health care industry, it is routinely necessary to sterilize, and maintain in a sterile condition, very large numbers of medical articles such as surgical instruments and the like. To this end, self-sealing pouches have been developed which are adapted to receive a medical article and be sealed, with the pouch and its contents then being subjected to sterilization such as by autoclaving, or by ethylene oxide gas or radiation exposure. The contents of the pouch are then maintained in a sterile condition until ready for use. Commonly-assigned U.S. Pat. No. 4,276,682, to Sibrava et al., discloses one such sterilizable pouch construction which has proven to be highly commercially successful.
In a similar regard, pouches and bags (sometimes referred to as dust covers) are also known which are suited for "sterility maintenance." Such pouches are usually adapted to receive an article after it has been sterilized (frequently while the article is still sealed within its sterilization pouch), and after sealing maintain the article in a sterile condition. Still other types of pouches are known which are suited for disposal of contaminated items.
It will be recognized that depending upon the intended use of a pouch, it is frequently important that the closing seal formed in the pouch after an article has been inserted therein be of high integrity, and prevent passage of contaminants. Therefore, it is not only desirable that a self-sealing pouch be configured to facilitate proper sealing (usually effected by hand), but it is frequently further desirable that the seal formed at the access to the interior of the pouch be secure as possible.
As is known in the art, the materials from which a pouch is fabricated must be appropriately selected for the intended use of the pouch. For example, some types of materials are suited for some sterilization processes, but not others. Additionally, pouch materials must be selected to assure their compatability with the adhesive employed for sealing the pouch, bearing in mind that the adhesive must be selected in accordance with government-established standards if the pouch is to be used for medically-related purposes.
In the past, these design parameters have acted to limit the flexibility of selection of pouch materials for self-sealing pouches. To assure sufficient useful shelf life for a pouch, pouch materials have been selected which, over time, do not lose their compatability with approved adhesives. For example, polyethylene plastic film must be corona discharge treated to assure its compatability with currently used approved adhesives, but this treatment deteriorates over time so shelf life is undesirably limited if the closing seal of the pouch is effected between the pouch's adhesive and its treated polyethylene film web.
Therefore, it is extremely desirable to provide a self-sealing pouch construction wherein an adhesive-to-adhesive closing seal is formed. In this way, the adhesive can be applied to the pouch during fabrication at a time when any required treatment of the pouch's web(s) has been recently effected to assure the integrity of the adhesive/web interface, with the adhesive-to-adhesive closing seal not being dependent upon the freshness of any web treatment. This permits the pouch web material to be selected without concern of excessive deterioration of its adhesive compatability over time.
In keeping with the above desired goals, the present invention entails a self-sealing pouch which is economically fabricated and very easy to use, and which is configured to provide a very secure adhesive-to-adhesive closing seal at the access opening of the pouch.